The dramatic and risky rescue at the Tham Luang cave in the northern province of Chiang Rai was launched on Sunday and four boys were brought out that day.
Four boys were rescued on Sunday.
"We're thankful for the coach for being there with them, to help guide the kids through this situation, without him, they probably wouldn't have survived", said Guerrero.
His announcement, at a news conference more than an hour after helicopters and ambulances were seen rushing from the cave area, drew cheers and applause.
The first boy left the caves at 5.40pm local time on Sunday 8 July. Some are not even strong swimmers, and have had to learn to dive in conditions that claimed the life of a former Thai Navy SEAL on Friday.
To make matters worse, rescuers are facing a "war with water and time" as unsafe monsoon storms and torrential rainfall could derail the mission.
Four schoolboys were rescued yesterday from the flooded cave where they had been trapped for 15 days with eight football teammates and their coach, marking a breakthrough in a remarkable operation watched by the world.
The rescue operation involved 50 foreign divers and 40 Thai divers.
All 12 Boys Have Been Rescued From Flooded Thai Cave
CNN was told the boys were exploring the caves on June 23 with their coach when they were trapped inside by heavy seasonal rains. Half of the boys attend school in Mae Sai, a community that borders Myanmar and lies just a few kilometres from the cave.
Multiple calls to senior government officials and military personnel leading the operation to rescue the members of the youth soccer team rang unanswered Monday evening. "Divers are expected to re-enter the caves in between ten and twenty hours" time because there were not enough air tanks along the route to continue, an official said.
The the next phase in the rescue operation is set for around 1-2pm (NZT) today at the earliest, involving a further three trapped boys, but an update from an Australian reporter at the scene says a downpour in Thailand today is creating concerns. It had been feared that sustained heavy rain could raise water levels inside the cave, greatly hindering the rescue operation.
He added doctors assessed they were "very fit physically and mentally..."
On Sunday night, Thai navy SEALs posted a celebratory note on their Facebook page, saying: "Have sweet dreams everyone".
Operations to rescue a trapped Thai soccer team began on Sunday, resulting in four rescues.
It was not immediately clear Monday how the overnight rains had impacted water levels inside the flooded cave.
"There are two obstacles, which are water and time", Narongsak said.
The local government said in a statement later on Sunday that 10 global divers had progressed into the cave and some had reached the point where the team is. "We can't visit our boys in hospital because they need to be monitored for 48 hours", Somboon told Reuters.
"Football's Coming Home. First Wild Boars Out", a headline on one online Thai paper said on Monday, referring to a song chanted by English soccer fans at the World Cup now underway in Russian Federation.
The 12 boys, aged between 11 and 16, and their coach, 25, went missing in Tham Luang Nang Non cave in northern Thailand's Chiang Rai Province on June 23.